Final answer:
The differential equation xy dy/dx = y² + 9 can be separated to integrate and find the general solution, which is y = 3 tan(3 ln|x| + C).
Step-by-step explanation:
To express the differential equation xy dy/dx = y² + 9 in the form ()=(), where ()=?, ()=?, and to provide the general solution of the differential equation, we must first separate variables and integrate. We can write it as:
dy/y² + 9 = dx/x
Next, we integrate both sides:
∫ dy/(y² + 9) = ∫ dx/x
The left side is a standard integral form that gives:
1/3 arctan(y/3)
The integral on the right side is a natural logarithm:
ln|x| + C
Therefore, equating the two results and solving for the constant C, we get the following general solution:
y = 3 tan(3 ln|x| + C)
This is the solution to the original differential equation.